Cardio A&P

• What makes up the inferior mediastinum?

  The anterior mediastinum, middle mediastinum, and posterior mediastinum.
• Contents of the superior mediastinum include?

  Thymus, great vessels (aorta, superior vena cava), trachea, esophagus, and nerves (vagus, phrenic).
• Anterior border of the superior mediastinum is the sternum and the posterior border is the IV disc of the T4-T vertebrae
• Contents of the anterior mediastinum include: thymus remnants, lymph nodes, fat, connective tissue, and sterno-pericardial ligaments.
• Anterior border of the anterior mediastrinum is body of the sternum and the transversus thoracis
• Posterior border of the anterior mediastinum is the pericardium
• Which section of the mediastinum is continuous with the superior mediastinum?

  Anterior mediastinum
• Contents of the middle mediastinum include: the heart, roots of the great vessels, main bronchi, and arch of the azygos vein
• Contents of posterior mediastinum include esophagus, thoracic aorta, azygos and hemiazygos veins, thoracic duct, vagus nerves, sympathetic trunks, and splanchnic nerves.
• Which mediastinum compartment is posterior to the pericardium?

  Posterior mediastinum.
• Pericardium is fused with the tunica adventitia of the great vessels and has sterno-pericardial ligaments
• Anterior (Sternocostal) surface of the heart formed mainly by the right ventricle.
• Inferior (Diaphragmatic) surface of the heart is formed mainly by the left ventricle and partly by the right ventricle; it is related to the central tendon of the diaphragm.
• Left Pulmonary Surface of the heart consists mainly of the left ventricle; it forms the cardiac impression of the left lung.
• Right Pulmonary Surface of the heart is formed mainly by the right atrium.
• Right border of the heart is formed by the right atrium and extending between the SVC and the IVC.
• Inferior border of the heart is formed mainly by the right ventricle and only slightly by the left ventricle.
• Left surface of the heart is formed mainly by the left ventricle and slightly by the left auricle.
• Superior surface of the heart forms the inferior boundary of the transverse pericardial sinus.  formed by the right and left atria and auricles in an anterior view
• What two arteries form an anastomosis surrounding the heart?

  The left and right coronary arteries.
• Originates from the right aortic sinus and follows coronary sulcus between atria and ventricles

  Right coronary artery
• Originates from the left aortic sinus and runs in coronary sulcus and gives off anterior IV and circumflex branches

  Left coronary artery
• The posterior descending artery: for supplying the posterior third of the IV septum
• What determines heart dominance?

  The PDA originating from either the right or the left coronary arteries.
• Coronary sinus is Main vein of the heart
• Coronary sinus receives from great cardiac vein on left.
• Coronary sinus receives from middle and small  cardiac veins at right
• Cardiac suction effect: the negative pressure created during ventricular contraction helps pull blood towards the right atrium.
• Describe the blood route into the superior vena cava?

  From the upper body and head, blood flows through the jugular veins and subclavian veins, which then merge to form the brachiocephalic veins. The brachiocephalic veins join together to form the superior vena cava.
• Describe the blood route into the inferior vena cava?

  Greater and lesser saphenous veins drain into the femoral vein, which drains into the external iliac vein which drains into the common iliac vein. The common iliac vein goes into the inferior vena cava.
• Elastic Arteries have Fenestrated elastic interspersed with collagen and smooth muscle.
• Both elastic arteries and muscular arteries have thick layer of tunica media
• What is the difference between muscular and elastic arteries?

  Elastic arteries have fenestrated elastic.
• Valves are made up of endothelium and connective tissues.
• Large veins have Thick adventitia and thin media
• Lymphatic capillaries are made up of a simple layer of endothelial cells with anchoring filaments holding open spaces
• Lymphatic vessels have tight junctions, but capillaries and veins do not.
• Patterned light (glycogen stores) and dark (smooth muscle) appearance is characteristic of purkinje fibers.
• Pacemaker cells are found in the conduction zones of the heart (SA node, AV node, Purkinje fibers, and bundle of His
• Pacemaker cells have slow acting response impulses